Odyssey Therapeutics filed terms for a $225 million initial public offering, the largest U.S. biotech debut attempt since June and the first autoimmune-focused listing since the FDA approved Johnson & Johnson's Tremfya expansion in Q3. Pricing is scheduled for this week, with trading to follow under the ticker ODTX. Renaissance Capital flagged the deal Monday morning.
The Cambridge company holds three preclinical programs targeting immunological disorders—two oral small molecules and one biologic—with lead candidate OTX-002 aimed at inflammatory bowel disease. No clinical data has been published. The company raised $332 million across three private rounds between 2020 and early 2023, the last at a $1.1 billion post-money valuation led by Fidelity and RA Capital. That round closed in February 2023, eighteen months before this filing. Founders include former Biogen and Genentech executives; the CEO previously scaled two Phase III programs at Bristol Myers Squibb.
The timing matters because autoimmune biotech has been shut out of public markets since mid-2023, when Organon's $180 million raise priced below range and fell 22% on day one. Odyssey's filing follows three straight quarters of positive pharma M&A prints—AbbVie paid $10.1 billion for ImmunoGen in November, Merck took Prometheus Biosciences for $10.8 billion in June—and a 34% rally in the SPDR S&P Biotech ETF since October lows. The company is offering 12.5 million shares at $17-19 per share, implying a $1.6 billion fully diluted market cap at midpoint. That represents a 45% step-up from the last private round, modest by 2021 standards but aggressive given the asset is still preclinical. Worth noting: the syndicate includes Goldman Sachs, Morgan Stanley, and Cowen, the same trio that priced Karuna Therapeutics at $16 in June 2019; Bristol Myers acquired Karuna for $14 billion in December 2023.
Allocators should watch three things. First, whether the deal prices in-range or below—biotech IPOs have printed below range in seven of the last nine attempts, signaling continued skepticism about early-stage valuations. Second, the three-month trading trajectory will determine whether Odyssey's success reopens the clinic-stage biotech IPO window; four companies with Phase I assets have confidentially filed and are waiting for a proof point. Third, OTX-002 is scheduled to enter Phase I trials in Q2 2025, with interim data expected by year-end—any enrollment delays or FDA feedback shifts will reprice the equity immediately. The secondary market for private biotech has been illiquid since SVB collapsed; this IPO gives late-stage venture funds their first real exit window in twenty months.
The deal prices Wednesday evening. If it holds at midpoint, Odyssey will be the fourth-largest U.S. biotech IPO of 2024, behind only Bicara Therapeutics ($362 million, April), Nextracker ($638 million, February), and Neumora Therapeutics ($250 million, March). All three are trading below issue price.